Films with patterned surfaces are made for a variety of applications. For example, photographic paper may include a film with a matte or glossy finish. This matte finish or glossy finish may produce a desirable effect on a photograph when viewed by a casual observer. A glossy or matte finish requires a photographic paper manufacturing process with certain tolerances (i.e. a certain level of precision). As tolerances of a manufacturing process become tighter, the manufacturing process generally becomes more complicated and expensive. In other words, the tolerances required to produce a patterned film for photographic paper may be significantly lower than the tolerances required to manufacture a light management film for a liquid crystal display.
A light management film may be used in a variety of applications. For example, a light directing film may be used as part of a liquid crystal display (LCD) to increase the power efficiency of the LCD. Increasing the power efficiency of a LCD (or other similar display) may be significant. Liquid crystal displays are often included in mobile devices (e.g. cellular telephones, laptop computers, digital cameras, etc.) which run on batteries. It is desirable for these mobile devices to maximize the operating time of their batteries. Although battery technology is improving, one way to increase the battery life of a mobile device is to reduce power consumption of the device without degrading quality. By making liquid crystal displays more efficient, the battery life of a mobile device can be extended, which is of great benefit to the user.
The optics of a light management film are very specific and detailed, compared to the optics of a glossy or matte finish on photographs. Accordingly, the precision of the manufacturing process for producing glossy or matte finishes on photographic paper may be inadequate for purposes of manufacturing light management films. For example, the manufacturing process used to manufacture other patterned films may not adequately reproduce optical elements of a light management film or provide a uniform thickness of the film, which may be required for a light management film to be usable. These inadequacies of previous manufacturing processes are critical considerations to the manufacturing of light management films.